Disclosed is a method of obtaining permeated water (produced water) by first supplying seawater to a reverse osmosis apparatus and then desalting the seawater, while obtaining salt by supplying concentrated water to an electrodialyzer and further concentrating the concentrated water in an evaporator (salt production) (Patent Document 1 and Patent Document 2).
Disclosed is a method of obtaining salt by first supplying seawater to an electrodialyzer and then concentrating concentrated brine in an evaporator, while obtaining permeated water by supplying diluted brine to a reverse osmosis apparatus (Patent Document 3 and Patent Document 4).
Patent Document 1: Japanese Patent Application Laid-open No. 9-276864
Patent Document 2: Japanese Patent Application Laid-open No. 2004-33848
Patent Document 3: Japanese Patent Application Laid-open No. 8-318136
Patent Document 4: Japanese Patent Application Laid-open No. 8-89958